I started CF and the Zone in Dec. I weighed around 375-380 lbs. I am now 313lbs. I am following Starting Strength and am now strictly Zoneish/Paleo. My goal is continued fatloss while building muscle and strength. I completed the physical agility test for the Sherrifs dept. on Sat. I passed the test which is amazing in it self. Couldn't have done it 6 months ago. However, I was told by the administrator that I needed to work on my aerobic fitness if I am accepted. I am still a big guy at 6'2. I don't want to tear my knees up. I've been doing some sprinting along with walking. Will the sprinting do the trick? Am I being to impatient? Is there something else I can do or need to consider?

What is your time frame? What is the distance? How much walking have you been doing? Times per week? Duration?

I know this is contradictory to what Steven said but I would NOT recommend sprinting yet until you lose more weight. You are very correct when worry about your knees/lower body.

__________________
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What is your time frame? What is the distance? How much walking have you been doing? Times per week? Duration?

I know this is contradictory to what Steven said but I would NOT recommend sprinting yet until you lose more weight. You are very correct when worry about your knees/lower body.

It has been varied. If I am hired the academy will start in Sept. so I have some time but I want to take advantage of it. I have been doing 8 roughly 100 meter sprints 3-4 times a week for the past month. Sprint from starting point 1oo meters and walk back to starting point and sprint again. I've been walking 1 to 1 1/2 miles on my off nites the past couple of months. Since Jan. I have been trying to keep in mind that I don't want to hurt myself or overdo the cardio.

I started CF and the Zone in Dec. I weighed around 375-380 lbs. I am now 313lbs. I am following Starting Strength and am now strictly Zoneish/Paleo. My goal is continued fatloss while building muscle and strength. I completed the physical agility test for the Sherrifs dept. on Sat. I passed the test which is amazing in it self. Couldn't have done it 6 months ago. However, I was told by the administrator that I needed to work on my aerobic fitness if I am accepted. I am still a big guy at 6'2. I don't want to tear my knees up. I've been doing some sprinting along with walking. Will the sprinting do the trick? Am I being to impatient? Is there something else I can do or need to consider?

If you've been told to work on your aerobic fitness then the answer is no, sprinting will not do the job. I presume that as you've completed the physical agility test you're anaereobic conditioning is already adequate for short bursts of activity so it's stamina that you need to improve and that's going to be a problem for someone who weighs 313lbs.
The first thing you need to do is get your weight down to a point where you can do some distance running without wrecking your knees and the most important aspect of achieving this is getting your diet under control so you can create a small negative energy balance and that's just a matter of applying some common sense and willpower to your food choices; lean meat and fish, vegetables, fruit, nuts and seeds are good, donuts are bad etc.
Distance running is going to be out of the question until you've lost some weight so I suggest you get a bike and just concentrate on building a good base level of aerobic conditioning which will help you lose some lard and limit sprint training to once or twice a week to save your knees. Any bike will do, it doesn't have to be expensive, in fact a cheap single-speed like most of us rode as kids is perfect for the job as it means you'll be forced to get out of the saddle and sprint more than you would if you had gears.
Once you've dropped some weight and you're aerobic conditionings improved you should start doing some running in the usual beginners mix of walking and running but if you feel any knee pain cut back on the distance running and get back on your bike so you can continue working on your aerobic conditioning and fat loss without risking injury.

Congrats! Im in the same boat actually. Down from just over 300 pounds to 250 as of Sunday. Ill be going into a sherrif's academy either this August, or Jan '09 depending on A - my preparedness (sp?) and B - if my connections can get me into the August academy (though it might be to late).

Until recently I havent ran since high school, need to get my time up to a 14 minute mile and a half. Not to mention all the running during training days.

Ive been following Starting Strength with the beggining runners program from runnersworld.com. Had to repeat the 'first week', 1-minute running (7.5 mph), 2-minutes walking (3 mph), for 4 weeks to work on form more than anything else, and no longer any expierence any ankle or knee pain. The program is an 8-week progression to a solid, 30-minute run. You might want to look into it.http://www.runnersworld.com/cda/smar...-278-0,00.html

Other than that, cant really offer much help, just tell ya what Im trying, though I still have some distance to go and am far from being an expert.

But again, congrats, I can tell ya from expierence, its a long, hard road, but your doing a damn good job.

Oh whoops, kind of glazed over the whole weight issue with knees thing. They're definitely right on that. Don't do too much yet.

Barbell complexes sounds like a good idea right now. Strong metabolic stress. As long as your diet and sleep is sound, the fat will keep on coming off.

Also, work on your running technique. NEVER land on your heels when you're running.

Darryl:

Sprinting WILL do the job for aerobic fitness *IF* the rest times are kept down. I'm not sure if you know much about the anaerobic vs. aerobic but as the sprinting volume drags on it will be more and more aerobic for energy.

I still recommend 400-800m intervals though. Those will rape you. HIIT is better for aerobic conditioning (provided enough volume but still less time than longer dirance running) than steady state running anyway. Well, at least for beginning and intermediate runners looking for aerobic conditioning + fat burn. One of the studies I looked at for HIIT vs. steady state showed that at 1/3 of the time for HIIT training (so for example, 20 minutes HIIT & 60 minutes steady state work) they had the same markers of fatty acid metabolism when all was said and done.

That's generally why metcon/hiit/tabata can complete with aerobic running in times for beginner and intermediate runners because they are significantly aerobic as the volume rises.

Oh whoops, kind of glazed over the whole weight issue with knees thing. They're definitely right on that. Don't do too much yet.

Barbell complexes sounds like a good idea right now. Strong metabolic stress. As long as your diet and sleep is sound, the fat will keep on coming off.

Also, work on your running technique. NEVER land on your heels when you're running.

Darryl:

Sprinting WILL do the job for aerobic fitness *IF* the rest times are kept down. I'm not sure if you know much about the anaerobic vs. aerobic but as the sprinting volume drags on it will be more and more aerobic for energy.

I still recommend 400-800m intervals though. Those will rape you. HIIT is better for aerobic conditioning (provided enough volume but still less time than longer dirance running) than steady state running anyway. Well, at least for beginning and intermediate runners looking for aerobic conditioning + fat burn. One of the studies I looked at for HIIT vs. steady state showed that at 1/3 of the time for HIIT training (so for example, 20 minutes HIIT & 60 minutes steady state work) they had the same markers of fatty acid metabolism when all was said and done.

That's generally why metcon/hiit/tabata can complete with aerobic running in times for beginner and intermediate runners because they are significantly aerobic as the volume rises.

Some of the scientificals might interesting, however totally useless to the OP.

Larry, you're making a huge investement in yourself, and your career. You're agile and likley quite strong but your weight loss goals have very specific challenges.

The best advice I can give you is to get some real (not internet based) support in reaching your goal. Find a coach who has worked with people in your situation or at least find a training buddy or group to push you, prefferbly folks with similar goals.